Novel marker for the detection of sickle cell nephropathy: soluble FMS-like tyrosine kinase-1 (sFLT-1).

BACKGROUND: Given the burden and poor outcome of end-stage renal disease in sickle cell disease (SCD), early markers of sickle cell nephropathy (SN) are desirable. Disordered angiogenesis underlies many complications of SCD. We aimed to determine the relationship between serum FMS-like tyrosine kinase-1 (sFLT-1) and other biomarkers of renal damage for the early diagnosis of SN. METHODS: Forty-seven SCD patients and 49 healthy controls were enrolled. Microalbuminuria was determined in patient urine samples. Blood samples were tested for sFLT-1, serum creatinine, and various hemolysis and inflammation markers. Peripheral blood monocyte expression of sFLT-1 was measured using real-time polymerase chain reaction (PCR). RESULTS: The serum level of sFLT-1 (pg/ml) in SCD patients was higher than controls (median/range/IQR = 142/ 60-1300/61 pg/ml vs. 125/ 110-187/52 pg/ml, respectively) (p = 0.006). Median (range) of sFLT-1 level was higher in SCD patients with microalbuminuria compared to SCD patients with normoalbuminuria, 185 (140-1300) vs. 125 (60-189) mg/g, respectively) (p = 0.004). There was a significant positive correlation between serum sFLT-1 and microalbuminuria, lactate dehydrogenase (LDH), and indirect bilirubin (r = 0.59, 0.39, 0.30, and p = <0.001, 0.007, 0.041, respectively). sFLT-1 sensitivity in early detection of renal affection in SCD was 93.6%, while specificity was 68.6%. Finally, peripheral blood monocytes (PBM) sFLT-1 expression was significantly higher in SCD patients compared to controls (p = 0.05). CONCLUSIONS: sFLT-1 may contribute to pathogenesis of albuminuria in SCD patients and constitute a novel renal biomarker of SN.

Influence of iron regulating genes mutations on iron status in Egyptian patients with sickle cell disease.

Mutations of the HAMP gene and HFE gene have a role in iron overload. We assessed the frequency of the G71D mutation of the HAMP gene and the H63D mutation of the HFE gene and the correlation between these mutations as well as the correlation between them and the iron overload in sickle cell disease (SCD) patients. Genotyping of G71D of HAMP and of H63D of HFE variants was performed by polymerase chain reaction-restriction fragment length polymorphism on 47 SCD patients and 45 controls. The iron status was assessed by serum ferritin and transferrin saturation. We found 61.7% of the patients had a wild genotype in both genes, 14.9% had a variation in HAMP-G71D, 27.7% had a variation in HFE-H63D, and 4.3% had variations in both. Patients with either HAMP-G71D or HFE-H63D variants did not show significant difference in iron status in comparison to patients with wild type genotypes. Multivariate regression analysis revealed that the number of mutations harbored by the patients tends to affect the serum ferritin level; p=0.07. Thus, The HAMP-G71D and HFE-H63D variants are not uncommon among the Egyptian SCD patients; neither of them alone was found to be a major determinant of iron overload in the studied patients. Nevertheless, the number of harboured mutations may increase the probability of iron overload in these patients.

Immunoregulatory cytokines gene polymorphisms in Egyptian patients affected with acquired aplastic anemia.

The immune system is thought to play an important role in aplastic anemia (AA) in light of recent findings of hematologic reconstitution after immunosuppressive therapy. T cell activation, apoptosis, and the cytokines interferon- and TNF-α are suspected to play a role in the suppression of growth of progenitor cells and induced apoptosis in CD34 target cells, TGFß is a multifunctional peptide, usually produced in latent form and requiring activation to produce a biological response. Also, TGF-ß1 has been described as an important negative regulator of haemopoiesis. Over production of IL-6 is described in AA but is of unknown pathophysiological significance. To investigate the role of cytokine gene polymorphisms (IL-6/-174, TNF-α/-308, IFN-γ/+874, and TGFß1/-509) in patients with acquired AA to assess if genotypes associated with higher or lower production were more prevalent than in established control population and to study the possible association of these genotypes with the disease severity. Fifty AA patients were included in this study. Polymerase chain reaction-amplification refractory mutation system (PCR-ARMS) technique was used to detect INF-γ single nucleotide polymorphism -874A/T, and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to assess IL-6-174 C/G, TNF-α-308G/A, and TGFb1-509C/T gene polymorphisms. Genotypes associated with high production of TNF-α, TGF-ß and IFN-γ, and IL-6 were more frequent in patients than in control; no association was found between the presence of hypersecretory genotypes and the disease severity.

Skin iron concentration: a simple, highly sensitive method for iron stores evaluation in thalassemia patients.

Iron overload is a potentially fatal complication in thalassemia patients. Accurate assessment of body iron is of utmost importance for these patients. The available methods for iron stores evaluation have limitations. We assessed biochemically the skin iron concentration (SIC) and determined the relation between the hepatic and skin iron level in thalassemia major patients to develop a simple, sensitive, quantitative measure of the body iron stores. Thirty-one cases with thalassemia major were assessed for iron overload. Liver and skin biopsies were performed for the patients and skin biopsies were taken from the 31 controls. The biopsies were subjected to biochemical assay of iron and histologic sections were examined. The SIC of the studied cases was significantly higher than that of the control group with a mean of 2.705 +/- 1.14 and 0.275 +/- 0.13 mg/g dry skin weight, respectively, p < 0.001. There was significant correlation between the SIC and the liver iron concentration (LIC) (r = 0.43, p = 0.01). The amount of liver iron is equivalent to [(3.5 x SIC) + 12.9]. With the use of this equation, we could reliably estimate an LIC value as high as 21.2 mg/g dry liver weight with a standard error of 4.07. Biochemical assay of the skin iron concentration is a reliable quantitative indicator of the body iron stores in patients with thalassemia major.